title: Ensemble and single-molecule detected time-resolved FRET methods in studies of protein conformations and dynamics.
abstract: Most proteins are nanomachines that are selected to execute specific functions and therefore should have some degree of flexibility. The driving force that excites specific motions of domains and smaller chain elements is the thermal fluctuations of the solvent bath which are channeled to selected modes of motions by the structural constraints. Consequently characterization of the ensembles of conformers of proteins and their dynamics should be expressed in statistical terms, i.e., determination of probability distributions of the various conformers. This can be achieved by measurements of time-resolved dynamic non-radiative excitation energy transfer (trFRET) within ensembles of site specifically labeled protein molecules. Distributions of intramolecular segmental end-to-end distances and their fast fluctuations can be determined, and fast and slow conformational transitions within selected sections of the molecule can be monitored and analyzed. Both ensemble and single-molecule detection methods can be applied for data collection. In combination with synchronization methods, time-resolved FRET was also used for studies of fast conformational transitions, in particular the folding/unfolding transitions.
authors.affiliation: The Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel.
authors.forename: Tomer
authors.initials: T
authors.lastname: Orevi
authors.forename: Eitan
authors.initials: E
authors.lastname: Lerner
authors.forename: Gil
authors.initials: G
authors.lastname: Rahamim
authors.forename: Dan
authors.initials: D
authors.lastname: Amir
authors.forename: Elisha
authors.initials: E
authors.lastname: Haas
mesh_terms: D004735:Energy Transfer; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D056004:Molecular Dynamics Simulation; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D011506:Proteins / Q000737:chemistry*
chemical_list: D011506:Proteins